Ok so I removed all my filters except for the metal sock in the tank just to keep the big chunks out of the line. So all I got now is the pump and regulator. I flushed all the lines and purged them. With the line disconected at the carb it flows evenly with incomming psi @ 3lbs and regulated side @ 0, but a nice healthy flow. But when I conect it to the carb it starts freeking out again; and ths is with the truck not running. And with the truck running it still does it. At one time with the truck not running and the lines all connected it did steady out, but when I let go of the switch and let it sit for a minute then hit it again it was back to being all jittery. So I disconnected the line at the carb again and just plugged it, same thing. I tried with and without the gascap and it made no diffrence. im lost. This setup worked great for 6 months or so. Ive replaced the pump and regulator and removed the filters; and its still doing it. What could I be missing?